On Sun, 1 Sep 1996, Ming-Ching Hsieh wrote:
> Dear Netters:
> I used a phosphate buffer, pH6.0 containing 3mM DTT and 10mM EDTA to
> equilibrate a DEAE-Sephadex column, but the resin was shunk to at least half
> of its original volume. I know the swelling properties of this resin are
> dependent on ionic strength and pH. Indeed, the pH of the eluent was only 4.1,
> suggesting a pH effect. More suprisingly, this effect seems irreversible
> since 0.05M sodium chlorid in distilled water can not regenerate the resin.
> The question is why EDTA changes the pH of this particular resin, and what's
> the mechanism of it. Any idea is appreiciated. Thanks in advance.
>>
My question is: Why are you using phosphate buffer for an anion-exchanger
and how are you dissolving EDTA at that low pH?
>>>>>>>>>>>>>>>>>>>>>>>>>>>
Dr. Hiranya S. Roychowdhury
Plant Genetic Engineering Lab.
Box 3GL, NM State Univ.
Las Cruces, NM 88003
Phone: (505) 646-5785
hroychow at nmsu.edu
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